Electrical furnace.



H. NATHUSIUS.. ELECTRICAL TURNACE. APPLICATION mmm 5116.25, 19ml` 'Patented Apr.2?,19o9.

Jlttj i 'Electrical Furnaces; and I do .HANS NATHUSIUS, Ol" ERIEDENSH '1"111, N EAR MO RGEN RUTH, GERM A N Y.

ELECTRICAL EURNAOE.

No. 92eme. Original application lcd Hay. il,I 1908, Serial To all whom 'it may conce/Mr.'

Be it known that l, IlANs subject of the King of Prussia, residing and having a post-office address iat Friedeiislii'ittc, near Moi'gcnroth, Germany, have invented a new and useful Improvement iii ei'eby declare'tlie following' to be al full, clear, and cxact description oi thesame.

The present ap lication is a division of an application Ser. o. 431,158,1i1ed 6th May 1908, for ,'Letters Patent of the United States.

This invention relates to an electric furnace of the kind described in my previous specification Ser'. No. 431,158 of 6th May 1908 which is destined for refinin andmanufacturing steel. S is" well' nown, the manufacture of good steel depends on a good and uniform heating of, the steel bath and on the .dbtainment of a slag which should be as hot and as luid` as possible and therefore `very suitable for reaction. 1 Existing furnaces do not compl with .these requirements, as on the one and, owing to the use of a small melting hearth, the steel bath has only a small surface of contact with the slag cover, further the expulsion of gases from the steel bath takes-place only with diieiilty and, lmoreover, in carrying out the necessary work in the surface of the bath, such as the frequent'removal of the slag by means of long ironrods, the stirring of the metal bath by means of wooden or steel bars, the distribution of the required additions on the surface jof the bath etc., diiiieulties are met with, because to enable such Work to be carried out, the electrodes which in the or dinary furnaces generally rest Yonl on the slag cover, must be raised, where y, `while the work iii ru'estion is being'carried out, the bath is co0 ed, as no current is passing through it. The carrying out of the above work while the current is passing is however difficult and complicated, as. the tools may come into contact'with the electrodesl and sometimes dis lace them, `and the bath is liable to get ii'ty owin` to the broken ofi pieces of the electrodes allinginto it, apart rom the fact that contact with such electrodes is dangerous to the life' of the attendants. f

The above disadvantages are obvi ted in" the urnaceaccording. to the speci cation Specification of Letters Patent.

No. 431,158. Divided and this application led August 190B. amai No. 450.213.

, ser No. 431',i I y NATiiUsiUs, a f trodes of alternate polarity being arranged i. i l

Patented April 27, 1909.

58 of 0th May 1908 by elecoii the circumference of the melting hearth, so that the electric current is forced to pass through and around the material contained in the melting hearth.

Accordingrl to this invention the electrodes projecting from the top into the furnace, are guided in parallel slots made in the cover of the furnace, so that they can be brought nearer together or farther apart from e cli other, wherebyT the resistance may be ncreas'ed `o,r reduced, so that 'accordingly a greater or smaller heat can befproduced.

4In the accompanyin drawings: Figure 1 shows diagrammaticaliiy a construction of the furnace according to this invention in vertical section, while Fig. 2 shows thesame construction in plan.

1 is a furnace covered by`an arch 2, the hearth 9 of which is made of some suitable refractory material 3. In the construction illustrated, two vertical electrodes a and c pass through the arch 2, while-into the bottoni space Aof the melting hearth penetrate the cooled electrodes d and j', The electrode c is connected to thenegative ole of a suitable source of electricity, and t ie electrode c to the positive pole. The' position Aas regards 'the two bottom ones is a reversed one, tlie electrode f being connected to thepositive pole, while the electrode d is'connected to the negative` ole. Owing to this arrangement of electro es, the current is forced rst to pass from the up e-r portion of the steel bathto tie electro e c. Secondly, from the bottom electrodef to theA liquidsteel situated at the bottom is also maintained hot. Moreover, owing to the current being forced to pass from the electrodes e and c, to the electrodes d and f at the upper electrode a through electrode d, whereby the the bottom, the bath itself is,- so to say, Vcompletely surrounded by electric currents of suitable heating power.

The electrodes a and c are'preferably not ma'de of carbon, but of some other material which, when the furnace is intended for manufacturing steel can be steel, but also some other material. These electrodes are hollow in order to enable them to be-cooled b circulat-ion of water through the pipe 4. The bott'oin electrodes are for\the saine purpose hollow and the which may be intro uced` wily wirbon would gol into the steel. Filliy,

means for cooling these electrodes are the sum ns shown um! doscriiwd in my specifiglttion, Heir. No. 43| ,15H of 6th May 1908.

The upper vlef'etrmlvs nre mndexdjustable in suitable slots 16 arranged in the cover 2 0f thc ful-nimo, in sut-Ii manner that they can be brought nwu'or lo, or fertili-r npnrt from euch m' vr, iwi-why tiw resistance is increased 0r rf Ancud, .w Lhut, :uw-urdingly n greater or nnilvr hvnl, run liv produced. If the elw trmivh' url' mmh of stoel, they cnn be dipped into the* inilii itsvlf, when the furnace 1s nlvmlwl for rl-iinivmr GL01-l, which ie impossible in 1| umsu of wirbnn electrodes ns in that the mutnl or itin-r vlcctrudvs do not Weurlds quickly am c-alrhon electrodos, they are better i conductors and do not cause any impurities in the bnth like the lutter owing to pieces chi ped ofi' etc'.

olim: In an electric furnace, u hearth, a cover therefor provided with slots, electrodes arranged to be uided by seid slots, and additional electro es to cause electric qurrent to ass through and around materiel contained m the hearth. l i

In testimony whereof I have si'gned my name to this speciation in the presence of two subscribing witn.

A HANS NATHeIUs.

Witnesseszi ERNST KA'rz, Enns'r BLmscn. 

